1. Field of the Invention
The invention relates to generating unique identifiers and more particularly relates to generating unique names for systems of devices, such as storage area networks, that do not automatically generate a name for the system of devices.
2. Description of the Related Art
Modern computer systems have driven a demand for enormous amounts of data storage. Data traditionally has been stored in one or more mass data storage devices, such as rotating magnetic disk drives or tape drives, attached to a single computer system. As computer systems have become larger, faster, and more reliable, there has been a corresponding increase in the need for storage capacity, speed, and reliability of the storage devices. Increases in the data storage capacity and reliability of storage devices have been dramatic in recent years. But despite the improvements to the devices themselves, there are certain limitations to what can be accomplished. Additional configurations of storage devices have increasingly been offered in recent years to meet demand for larger capacity, faster, more reliable, and more accessible data storage.
One example of alternative configurations is the rapidly increasing popularity of “RAID” systems, i.e., redundant arrays of independent disks. A RAID system stores data on multiple storage devices in a redundant fashion, such that the data can be recovered in the event of failure of any one of the storage devices in the redundant array. RAID systems are usually constructed with rotating magnetic hard disk drive storage devices, but may be constructed with other types of storage devices, such as optical disk drives, magnetic tape drives, floppy disk drives, etc.
Another example of a storage alternative is the concept of a storage subsystem. A storage subsystem implies a greater degree of independence from a host computer system than is typically found in an isolated storage device. For example, the subsystem may be packaged in a separate cabinet, with its own power supply, control software, diagnostics, etc. The subsystem may have a single storage device, but more typically contains multiple storage devices. The notion of a storage subsystem and a RAID system are not necessarily mutually exclusive; in fact, many RAID systems are constructed as semi-independent storage subsystems, which communicate with a host through a communication link having a defined protocol. It is possible in such subsystems that the host is not even aware of the existence of multiple data storage units or data redundancy in the storage subsystem. To the host, the subsystem may appear to be a single very large storage device.
Another example of a storage alternative is a Storage Area Network (SAN). SANs involve moving network storage from its traditional location—inside, or directly connected to, file servers—to a separate network of its own. Disk, tape, and optical storage can then be attached directly to this network, which is based on a fabric of fibre, switches and hubs that connects storage devices to a heterogeneous set of servers on a many-to-many basis.
A SAN is a dedicated storage network that carries I/O traffic only between servers and storage devices. A SAN can also enable direct storage-to-storage interconnectivity, and lends itself to the exploitation of new breeds of clustering technology and to getting the best out of network attached storage devices that can intelligently provide disk and tape capabilities to one or more servers. SANs provide continuous client availability to storage devices if a server in the loop fails, and some backup solutions are capable of replicating data and application files in real time to secondary servers on the SAN.
In order to manage SANs, each SAN must be associated with a unique identifier. This unique identifier allows a user to identify particular SANs within a local area network. Typically, the fabric of switches that comprise the SAN calculates the unique identifier internally. However, a problem arises when a fabric comprises switches that do not internally calculate a unique identifier. Without a unique identifier, a user is unable to properly identify and manage a particular SAN. Other systems of communication devices may experience similar difficulties.
From the foregoing discussion, it should be apparent that a need exists for an apparatus, system, and method that generate a unique name for SANs and other systems of communicating devices that do not automatically generate it. Beneficially, such an apparatus, system, and method would provide a unique identifier for a system based on the fabric of switches that comprise the system.